function logout() {
	let postaddress = '/logout';
	$.ajax({
		//几个参数需要注意一下
		type: "GET", //方法类型
		dataType: "json", //预期服务器返回的数据类型
		contentType: "application/json;charset=utf-8",
		url: postaddress, //url 
		success: function(result) {
			if(result.code === 0) {
				localStorage.removeItem('user');
				window.location.herf = 'Login.html';
			}
		},
		error: function() {
			alert("错误");
		}
	});
}